/*
 * @lc app=leetcode.cn id=63 lang=cpp
 *
 * [63] 不同路径 II
 */

// @lc code=start
class Solution {
public:
    int uniquePathsWithObstacles(vector<vector<int>>& obstacleGrid) {
        int m = obstacleGrid.size();
        int n = obstacleGrid[0].size();
        vector<vector<int>> dp(m, vector<int>(n, 0));
        for(int i = 0; i < n; i++)
        {
            if(obstacleGrid[0][i] == 1)
            {
                break;
            }
            dp[0][i] = 1;
        }
        for(int i = 0; i < m; i++)
        {
            if(obstacleGrid[i][0] == 1)
            {
                break;
            }
            dp[i][0] = 1;
        }

        for (int i = 1; i < m; i++)
        {
            for (int j = 1; j < n; j++)
            {
                if(obstacleGrid[i][j] == 1)
                    dp[i][j] = 0;
                else
                    dp[i][j] = dp[i - 1][j] + dp[i][j - 1];
                
                // printf("dp[%d][%d] = %d\n", i, j, dp[i][j]);
            }
        }
        return dp[m - 1][n - 1];
    }
};
// @lc code=end

